Viruses cause a variety of illnesses. For example, influenza A viral infection involves one type of virus that causes group infection and epidemics around the world, and that often presents severe conditions for children, the elderly, and persons with cardiopulmonary diseases or immunodeficiency. (Refer to non-patent literatures 1 to 3.).
No reliable and effective remedy for viruses has yet been discovered during the development in recent years of various drugs. Currently, although inoculation with inactive vaccine has been used as an effective means, the influenza A virus, for example, has effectively altered its superficial antigenicity, and the therapeutic effectiveness of the vaccine is often reduced.
There have been many recent reports on the in vivo or in vitro effectiveness of chemotherapy on viral infections when using the new drugs zanamivir and oseltamivir (Refer to Non-Patent Literature 4 through 8.), which are neuraminidase inhibitors, as well as drugs such as amantazine and rimantadine, which are ion channel blockers.
However, there have been reports (Refer to Non-Patent Literature 9.) that these are only effective when administered during early infection, and cannot prevent pneumonia and secondary infection, and resistant viruses have been reported.
In this regard, heat shock protein (hereinafter referred to “HSP”) belongs to the group of stress proteins induced in the cell under various kinds of stress, and the most notable phenomenon in this area is a heat shock protein with a molecular weight of 70 kD (hereinafter referred to “HSP70”). Recently, a wealth of research has focused on this topic, and there have been many reports of the protective effects of heat shock protein in relation to the living body and cells.
HSP has an anti-inflammatory action in relation to lipopolysaccharides, suppresses inflammatory cytokine, has an effect to protect from ischemia, and suppresses cellular apoptosis, therefore, from the perspective of protecting the body from attack, HSP shows promise for treating a variety of diseases such as septic shock, and ischemic conditions of vital organs such as the heart and brain.
However, there is no practical method to induce HSP for clinical applications, since the induction is based on the environmental stress such as heat shock, sodium arsenate and heavy metals, or on the disease stress such as ischemia. No method to safety induce HSP in the body has yet been established.
In recent years, there have been reports that the mechanism of action of geranyl-geranyl acetone (hereinafter referred to “GGA”. Product name “Selbex”, manufactured by Eisai Co., Ltd.) is mediated through the induction and expression of HSP. (Refer to Non-Patent Literature 10.) For this reason, GGA is gaining notable attention as a clinically applicable HSP inducer.
Thus, an object of the present invention is to provide a new drug for viruses by focusing on the strong HSP inductive action of GGA, and by studying the infection preventive and therapeutic effects in relation to viruses.
Non-Patent Literature 1:Glezen WP. Epidemiol Rev. 1982; 4: 25-44;Non-Patent Literature 2:Couch RB, Kasel JA, Glezen WP, et al. J.Infect Dis. 1986; 153: 431-40;Non-Patent Literature 3:MMWR Morb Mortal Wkly Rep 1997;46(RR-9); 1-25;Non-Patent Literature 4:Woods JM, Bethell RC, Coates JA, et al.Antimicrob Agents Chemother1993; 37: 1473-9;Non-Patent Literature 5:Hayden FG, Osterhaus ADME,Treanor JJ, et al.N Engl J Med 1997; 337: 874-80;Non-Patent Literature 6:Gubareva LV, Kaiser L, Hayden FG, Lancet2000; 355(9206), 827-35;Non-Patent Literature 7:Long JK, Mossad, Goldman MP, Cleve Clin JMed 2000; 67: 92-5;Non-Patent Literature 8:Wingfield WL, Pollack D, Grunert RR,N Engli J Med 1969; 281: 579-84;Non-Patent Literature 9:Wingfield WL, Pollack D, Grunert RR,N Engli J Med 1969; 281: 579-84;Non-Patent Literature 10:Hirakawa T, Rokutan K, Nikawa T, et al.Gastroenterogy 1996; 111: 345-57.